Onan 5 KW 120/240 Volt Generator

Jon - Don't know, missing battery and the pull-rope looks like it's dry rot, right now just trying to find-out, it's value. My neighbor won't be back until Wednesday night, hopefully he can give some history about it, "like when was it last running". Because it has a metal enclosing everything on the inside is in fairly good shape. The gas tank still has about a 1/4 tank of fuel, I'm sure that's not usable. I'll pull the plugs latter today. I wouldn't mind having this as a backup electrical supply. I already have two small Honda's, that basically can give me lights and run a TV, but not big enough to run the refrigerator. This Onan, could easily keep the beer cold and lights too! Just not into any extra projects right now.

Found a really interesting web forum called "Smokstak" - A antique engine forum, covers a lot of territory! Steam, gasoline and diesel engines. Also cars, trucks, motorcycles, tractors, generators, pumps and industrial machines. One of the other things I found in this pile of "junk", was a old John Bean two piston pump. I think this will have some value to the right collector of old machines. These pumps were used in everything from "orchard sprayers" to firetrucks. The John Bean Company, became the FMC Corporation, all from his invention of this pump.

Anyway looking for information about this pump, I found "Smokstack", it told everything about the pump. Then started checking out other sections of this forum, found the generator section. A great resource for all things "old" related to machines. Was able to download the operating and maintenance manuals for the generator.

Highly recommend this forum to all SMF members wanting info on old machines.

Like everything else check ebay for active/completed and sold. Be certain you look for parts selling. I would consider using a socket to turn it over before hooking up a battery. If it turns over I tend to thing someone will be interested in it.



One day when I can afford it I will buy a stand by generator for my home. My wife the dogs and I really like air con and cold drinks. Mike

they made generators for rvs too just random info and a possible direction for research

Bert:

The best source of info on Onans that i know of is Bruce Perrault of Precise Engine Repair. He had something like 40 yrs of experience with them before he retired a few years ago. He used to sponsor a small engine repair forum where you could ask questions but i don't know if it's still up. The closest link i could find to get you in contact with him was this:

Wildflowers Home - Central Washington Wildflowers

Gawd .... those old ONAN's were wonderful machines. Real honest to gosh American quality built for continuous duty use. Not at all like the emergency service crap that they're building these days.

Sadly .... they're something from a bygone era. They have huge sentimental value but they're obsolete in this day & age. There are four problems:

1: Even though they were of incredible quality & built to last forever there's no money in selling obsolete parts. When Cummings bought out ONAN for the name they quickly distanced themselves selling parts & shifted manufacturing to China. From what i've heard it's difficult to get repair parts through them.

2: As wonderful as they are they just don't meet the clean air -or- noise standards of today. That would be particularly so where you are because Cali is known for extremism on environmental quality standards.

3: The ONANs were built in a day and age when oil was cheap. Gasoline was only 25 cents a gallon and nobody gave a second thought to energy efficiency. Engine designs have come a long way since then.

Cost to operate is a major consideration. You're talking serious bucks to run a little 5kw twentyfour/seven for a week or more during an outage. Your local city ordinances might not allow you to store enough fuel to keep it running for more than half a day. Best guess is that it would suck through 1 GPH at 75% load. At 3.00 $/gallon it would probably cost somewhere around 60.00$ a day for electricity.

4: Check your 220 outlet on the machine. There's probably two hots and a ground ? ( 3 prongs total)

Electrical codes changed sometime back around y2k. Today's standard is four wire. ( 4 prongs total) I think they added a requirement for a safety neutral ? You might run into some hassles with the building inspector if you tried to hook it up to your house. Depends on how stringent they are where you live.

All around .... a lot of things to deal with when putting it back into service ?

Edited to add:

Memory was vague because it's been awhile but you want to check the voltage output on each of the 110 volt legs if you can get the generator running. I think they need to be within 5 % of one another ? It's been so long that i've mostly forgotten but there was a procedure for adjusting the output of each leg on some of the ONANs. It would help if you could locate a service manual for that particular model.

Also ... verify that it's running at 60 hertz and not 50 hertz. Should say somewhere on the metal tag that lists the model # & specs of the generator.

Scrapah - Thank You! I didn't think about fuel efficiency, AQMD regulations (Air Quality Management Board), and parts availability. When this generator was made, most of us had never heard of OPEC and $5 could buy more than a half a tank of fuel. Muscle cars, with big block engines, 4 barrel carbs, and speedometer's that went pass 120 mph.

Where I live the AQMD regulates all sources of air pollution and this generator, I doubt would pass their scrutiny. Here they regulate lawn mowers. fireplaces, dust from construction sites and just about everything concerning air quality.

Parts from Cumin's - Onan would not be obtainable, as I have already checked. They only sell the air and oil filters for this machine. There are companies that sell used, refurbished, and after market parts though.

The good news is this generator is all there with the only thing missing is the battery. There is a lot of people that still like these old machines. The old Onan generators almost have a "cult" type of enthusiast from my internet researches.

I don't have a eBay account and have had very little success with selling on craigslist. I'm going to try to sell it on craigslist, maybe with this being one of their largest markets, I'll get lucky this time!